There is a temptation to take that line from Jack Nicholson — snarled at Tom Cruise in “A Few Good Men” —as the moral of the story, the lesson to be learned from a new study on trustworthiness and the news media.

The study, conducted by the nonpartisan Pew Research Center, informs us that America’s least-trusted news source is conservative radio talk show host Rush Limbaugh, rated unreliable by almost 40 percent of all Americans. The also conservative Fox News follows closely at 37 percent. So America’s least-trusted news sources are also its most popular; Limbaugh hosts the number one show on radio and Fox is the highest-rated cable news outlet.

It gets better. Pew tells us America’s most trusted news source is CNN; the network that eschews any ideological identifier is considered reliable by 54 percent of us. Yet for as much as we supposedly trust it, we don’t seem to like it very much. Its ratings — despite a mild resurgence in recent months — are but a fraction of Fox’s and it is undergoing massive layoffs.

For what it’s worth, there’s evidence to support America’s perception of who is and is not trustworthy. PunditFact, an offshoot of PolitiFact, the Pulitzer Prize-winning fact-checking website, has issued a report card on the truthfulness of broadcast pundits by network. It’s an imperfect measure, but the results are still compelling. Over 60 percent of Fox pundit statements rated by PunditFact have been found to be some flavor of false.

CNN? Just 22 percent.

If all this sounds like a commercial for the network of holograms and missing plane obsessions, it isn’t. Rather, it’s a lament for the closing of the American mind.

There is an axiom that he who builds the best mousetrap enjoys the greatest success. But if that’s true, how is it the greatest successes in a business measured by trustworthiness are those entities judged least trustworthy of all? Maybe the answer is that conservative hardliners are more rabid in support of those who validate their views than the rest of us are in pursuit of simple truth.

In a nation where political discourse is increasingly a facts-optional exercise and reality now comes in shades of red and blue, that’s hardly reassuring.

Two years ago, at the request of yours truly, the people at Nielsen crunched some numbers. They found that in times of major breaking news — the examples used were the Columbine shooting, the Sept. 11 attacks, the commencement of the Iraq War, the Japanese tsunami and the death of Michael Jackson — ratings for all three cable news outlets tend to rise. But, almost without exception, the most dramatic spikes on a percentage basis are enjoyed by CNN. The week of Sept. 11, its ratings rose by 800 percent. No other network came close.

In other words, when something big has happened and people need to know what’s going on, they know where to go. They go where they can trust.

But on a routine day, many Americans, for as much as they will say otherwise, really don’t want to be informed so much as to be confirmed in their political biases, in the partisan version of truth that explains the world to them while making the fewest demands on intellect — and conscience. They need the “death panels” and “anchor” babies, the birther controversies and supposedly rampant voter fraud, the “threats” of sharia law and Obama-caused Ebola, the whole rickety structure of falsehood and fear upon which conservatism has built its alternate reality. That’s the whole reason Fox exists — and CNN barely does.

And it’s why Nicholson’s quote, tempting as it is, provides no proper moral for this story.

It’s not that we can’t handle the truth. It’s that some of us prefer the lie.